The present invention refers to a shiftable pedal bearing gearing for a bicycle or the like.
German Patent No. DE-A 38 27 819 discloses a shiftable pedal bearing gearing for a bicycle or the like, which includes a crank axle supported in a pedal bearing housing and operatively connected at both axial ends to a pedal crank. The crank axle supports a chainwheel, a disk arranged parallel to the chainwheel and engaging at least one toothed planet gear for supporting the latter, as well as a coupler. A switch shaft is set coaxially within the crank axle and linked to the coupler in such a manner that a slight pressure upon the switch shaft in axial direction shifts the coupler for connection with either the chainwheel or the disk in a form-fitting manner to effect respective switching operations and to change the speed.
U.S. Pat. No. 5,303,942 discloses a similar pedal bearing gearing for a bicycle or the like, in which the chainwheel and the disk are provided with several circumferentially spaced recesses for effecting a play-free, force-transmitting connection. Each recess of the chainwheel and each recess of the disk is of stepped configuration to define a first recess section and a second recess section, with the coupler in a first stage engaging the first recess section with play and in a second stage snugly fitting in the second recess section with no play.